Google Glass is still a huge question mark. Samsung's Gear Fit isn't reliably accurate. Fitbit had to issue a recall for its flagship activity tracker. And now the world waits for Apple to release an iWatch--because only Apple, apparently, can fix the broken smartwatch paradigm.

Yet in its simple, two-trick-pony earphone gadget, LG seems to have delivered on the promise of its product packaging. No, the HeartRate Earphones don't run apps, or tell the time, or respond to voice commands. But they play music and monitor your heart rate--ostensibly with a high degree of accuracy. And that's all they need to do.

Science and ergonomics

Intel showed off a prototype of heart-rate monitoring earphones at CES in January, but LG is the first company to bring this type of technology to market.

Priced at $180, the system places a spectroscopic blood-flow sensor directly in the right earbud. It's an approach that offers greater accuracy than competing wrist-worn heart-rate sensors, LG says. In fact, the company maintains its system is just as accurate as traditional chest-strap sensors, and deviates from the accuracy of hospital electrocardiogram machines by no more than 7.4 percent.

The Earphones are a bit difficult to get on, and I still haven't mastered the process after three days of frequent use. Each asymmetrically designed phone is marked L and R, but you have to finagle what LG calls a sharkfin into the antihelix of your outer ear, and then wind a semi-rigid ear loop around your entire fleshy mass.

Yeah, I make it sound really awful. But once the Earphone are attached, they're as comfortable as any earbuds. The Earphones connect to your smartphone via Bluetooth, which means you don't have to stay directly tethered to your handset to listen to music. You will, however, have to clip the system's main controller to a piece of clothing or hold it in your hand. Also consider the system will stop working if run out of battery life, which is rated at four continuous hours of heart-rate monitoring and/or music playback.

Data and audio quality

I'll share more thoughts on the veracity of LG's heart rate data in my final review, but for now I'm willing to state that I believe the system is more than sufficiently accurate for recreational exercise tracking. I used the Earphones for three separate 30-minute workouts on my elliptical machine, and LG's real-time heart rate feedback scaled evenly and logically with the intensity of my exercise.